Automatic gas control



April! 29, 1924. 11,492,278

G. A. TUCK AUTOMATIC GAS CONTROL Filed March 2. 1923 2 Sheets-Sheet 1 111mm;- o 'mzi z Mg April 29 1924.

1,4922 78 s. A. TUCK AUTOMATIC GAS CONTROL Filed March 2. 1923 2 Sheets-Sheet 2 Airy reamed pr. 29, 1924.

STATES 1,492,27 lCE PATENT AUTOMATIC GAS CONTROL.

Application filed March 2, 1923. Serial No. 622,421.

To all whom it may concern:

Be it known that I, Gnonon A. Took, a citizen of the United States, residing in the city and county of San Francisco and State of California, have invented a new and useful Improvement in Automatic Gas Controls, of which the following is a specification.

My invention relates to improvements in automatic cut-oil's for gas burners and the like wherein a pilot burner is connected with a cut off valve and arranged to normally maintain said valve open while the pilotflame is burning, and to close said valve should the pilot flame become extinquished.

The primary object of my invention is to provide an improved automatic cut-ofl' for gas burners.

A further object is to provide a device which may be readily installed in connection with gas burners of various descriptions.

A further object is to provide an improved arrangement whereby the gas control may be readily set in an open condition and rigidly maintained in such condition so long as the pilot light is burning.

Another object is to provide an improved construction which may be readily adjusted to compensate for wear.

A still further object is to provide an improved construction which may be cheaply constructed and which may be connected with existing installations with a minimum of labor and expense.

I accomplish these and other objects by means disclosed in the drawings forming a part of the present specification wherein like characters of reference are used to designate similar parts throughout the said specification and drawings and in Which Fig. 1 is a broken front elevation partly in vertical section of one form of gas burner, showing the application of my improved pilot light in connection therewith.

Fig. 2 is a broken side elevation of my improved pilot burner showing the connection with a cut-off valve and the operation thereof when the gas is extinguished.

Fig. 3 is an enlarged detail of the valve securing means. i

Fig. 4: is a broken detail partly in vertical section showing the lower portion of the pilot light as viewed from the right of as burners which are operated in connection with heating system,- hot water heaters, and many other devices wherein the main burner is more or less frequently turned on and off, are commonly equipped with a pilot burner connected with the gas supply and arranged to burn a small 'et of gas at all times, said pilot burner eing mounted in relatively close proximity to the main burner and the jet directed thereover so that as soon as the gas is turned on the gas issuing from the burner will be ignited. However, as the gas frequently collects above the burner in suflicient quantity to cause a slight explosion when ignited, it often happens that the pilot flame is extinguished. Thus when the burner is turned off and later again turned on, the flame of the pilot burner having been extinguished, the gas issuing from the burner will not be ignited and as a result the inflammable gas will collect in and around the burner to an extent greatly endangering life and property.

To insure against this danger I have provided an improved device wherein the pilot burner normally operates in the usual manner to ignite the gas issuing from the burner. but is characterized by the provision of means for automatically cutting of? the gas supply to the main burner should the pilot flame. be inadvertently extinguished.

Referring particularly to the drawings my invention will be seen to consist of a pilot burner formed from a tubular member 1, mounted within a gas heating device 2 provided with a gas burner 3, of any suitable character to which gas is fed through a supply conduit 4. A flanged cap 6 is threaded or otherwise secured uponthe upper end of the tubular member 1, said cap having radially disposed apertures 7 formed immediately below the flange. A rod 8 is secured at one end to the cap 6, preferably by threading into a suitable threaded aperture formed in the top of said cap, said rod extending through the tubular member.

The end of the tubular member 1 op osite the cap 6 is provided with a suitable tting 9, having an opening 10 arranged to receive an apertured plug 11, forming a close slidm ll ing fit with the rod 8 which is extended outwardly therethrough. An open ng 12 in the side of the fitting 9, is arranged to receive a fitting 13 to which is connected one end of a conduit 14. The other end of the conduit 14 is connected through a suitable gas cock 16 with the supply conduit 4 whereby gas is directed from said supply conduit to the trol valve 20 and may be of any standardv construction, a type wherein a lever 18 mounted upon a lateral extension is arranged to actuate a closing member within the valve being shown in the drawingsby way of illustration, but as the mechanism of the valve forms no part of the present invention a detailed illustration or description is omitted.

A slotted member 19 is slidablymounted upon the outwardly extending end of the rod 8,said member 19 being arrangedto be normally held against the outer end of the plug 11 by means of a clamping member 21, mounted upon the outer end of the rod 8, and having a slight pivotal movement thereof. The clamping member 21, is held upon the rod 8, by means of a nut 22, a washer 23 be being mounted between the nut and the member 21, to provide an adequate bearingsurface for the clamping member, and a retaining nut 24 threaded onto the end of the rod 8, to retain the nut 22 in a desired position upon the rod. The member 19 is apertured at one end thereof to receive one end of a connection 26 secured between the lever 19 and said slide member 19. The lever 18 is actuated by gravity to move the lever to a closing position. The lever 18 is normally held in an open position by means of the connection 26, the slide member being held against the plug 11 by the clamping member 21, after said slide member has been moved to a position causing the lever 18 to be moved to a desired elevation.

The tubular member 1 above described is made of suitable material having a high co efliciont of expansion, The rod 8 is made of material having a lower coefficient of expansion than that of the tubular member so that when the two are heated a greater expansion will occur in the tubular member than in the rod. In practice I find that by making a tubular member of brass and the rod of steel a satisfactory result is obtained, but other metals or alloys may be of course substituted if desired.

The pilot burner is initially adjusted while cool by means of the nut 22 which is moved to such a position that a cam surface 25 formed upon the clamping member 21 will engage the under surface of the member 19 and hold said member 19 lightly against the lower end of the tube 1 or plug 11, but not with suflicient pressure to resist the pull of the weighted lever 18 against the member 19. The clamping element 21 is provided with a handle portion 28 by which it may be pivotally moved upon a fulcrum point 29 whereby the cam surface may be caused to release all pressure against the member 19.

In operation my invention is as follows. The pilot burner being mounted in any suitable manner in connection with the supply pipe and adjusted as above described, the cock 16 is opened and the gas, which will then issue from the apertures 7, ignited. The heat of this burning gas issuing directly below the flange of the cap 6 will cause said cap to quickly become heated, the conductivity of the metal causing heat to be imparted to the tubular member 1 and to the rod 8. As the member 1 and 8 become heated an expansion will occur. The tubular member, having the greater coefficient of expansion, will expand a greater amount than the rod 8, the difference in expansion of these two members causing the clamping element 21 to be drawn tightly against the member 19 which is thereby rigidly clamped against the lower end of the tubular mem- I After the pilot burner has been allowed to burn sufficiently long to thoroughly heat the burner, the wei hted lever 18 is elevated to open the valve 1 and the member 19, moved along the rod 8 until the connection 26 is drawn tight, the clamping element 21 being previously moved to the position shown in full lines in Fig. 3 to permit free movement of the member 19 to the desired position. The clampin element is then moved by means of the andle portion 28 to theposition shown in dotted lines in Fig. 3, thereby causing a clamping pressure to be applied against the member 19 which member and the valve lever 18 are thereby maintained in the normal operative position shown in full lines in Fig. 2. So long as the pilot burner remains lighted and the members thereby maintained in their heat expanded condition, the member 19 will remain clamped in position and the burners will operate in the well known manner. However, should the pilot flame become extingushed, the tube 1, and rod 8 will immediately begin to cool and as soon as the resulting contraction causes the members to return to their normal condition the pressure caused by their unequal expanslon will be relieved and the weighted lever 18 thus permitted to drop to a valve closing position, as shown in dotted lines in Fig. 2, thereby closing the cut-off valve 17 and preventing the passage of further quantities of gas to the burner 1 It is thus seen that so long as the' pilot burner is lighted the main burner 3 can be controlled by a thermostatic or other character of control valve 20 in the usual manner, but when the pilot burner is extinguished the supply is cut off entirely independently of such valve 20 and the escape of gas prevented in the event the burner control valve is opened before the pilot is again lighted and the cut-off valve 17 reset in the manner above described.

The cut-0E valve 17 may be closed While the pilot burner is burning by manually moving the clamping element 21 to release the pressure upon the element 19, the throw of the cam surface 25 when the element is moved to the position shown in full lines in big. 3 being suflicient to cause the member 19 to be disengaged even when the tubular member and the rod 8 are fully expanded by heat.

The precise construction and relation of parts above described is of course subject to modification in a great number of ways to conform to the requirements of different types of burners and burner installations. I therefore do not desire to restrict myself closely to precise disclosure herein contained, but wish to avail myself of such modifica tions as may fall within the scope of the appended claims.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is:

1. The combination with a gas'burner, a supply pipe, and cut-01f valve mounted in the supply pipe for controlling the flow of gas through the pipe to the burner, of a pilot burner mounted adjacent the burner, said pilot comprising a tubular member connected to the supply pipe and having an opening arranged to direct a jet of burning gas over the burner; a rod extending through the tubular member, said rod being secured in one end of the tubular member and slidably engaged at the other end thereof; a member slidably mounted upon the rod, said member being connected to the cutoff valve; and means mounted upon one end of the rod for clamping said sliding member against the tube to maintain the valve in open position When the tube and rod are expanded by the heat of the burning flame, said means being arranged to release said slide member when the members contract upon cooling of the parts thereof when the pilot flame is extinguished.

I 2. The combination with a gas burner, supply pipe, and cut-01f valve mounted in the supply pipe for controllin the flow of gas through the pipe to the urner, of a pilot burner mounted adjacent the burner,

said pilot burner comprising a tubular member connected to the supply pipe and having an opening arran ed to direct a jet of burning gas over the urner; a rod extending through the tubular member, said rod being secured within one .end of said tubular member and extending throughthe other end of said outward member and in sliding engagement therewith; a member slidably mounted within the burner and upon the outwardly extending end of said rod and connected to the cut-off valve; and ad ustable means mounted upon the outer end of the rod and actuated by unequal expansion of the rod and of the tubular member when heated by the burning et, for clamping said slide member against the tubular member to normally retain the cut-off valve in an open position and to automatically release said slide member when the tubular memberand rod are contracted upon cooling after the pilot flame is extinguished.

3. The combination with a gas burner supply pipe, and cut-ofi valve mounted in said supply pipe for controlling the flow of gas through the pipe to the burner, of a pilot burner mounted adjacent the burner, said pilot burner comprising a tubular member arranged to direct a jet of burning gas over the burner; a rod extending through the tubular member, said rod being secured Within one end of the tubular member and extending outwardly through the other end of the said member and in slidable engagement therewith; a slotted member slidably mounted upon the outer end of the rod and connected to the valve; a clamping member mounted upon the rod; and means mounted upon the outer end of said rod for bolding the clamping member in proximate relation to the slotted member, said slotted member being slidable between; the clamping member and the end of the tubular member when the rod and tubular member are cool and rigidly clamped between the clamping member and the tubular member due to unequal expansion of said rod and tubular member, when heated by the burning jet, whereby the valve may be maintained in open position while the pilot is burning and released to a closed position when the pilot is extinguished.

4. The combination with a gas burner, supply pipe and gravity actuated cut-ofl valve, mounted in the supply pipe for controlling the flow therethrough to the burner, of a pilot burner mounted adjacent the burner, said pilot burner comprising a tubular member; a cap secured upon one end of the tubular member and apertured to direct burning gas therefrom over the burner; a rod extending through the tubular member, said rod being secured at one end upon the cap and extending outwardly through the o posite end of the tubular member in slida le engagement therewith, the rod and tubular members being made of metals adapted to cause a greater expansion of the tubular member than of the rod when heated by the burning jet; a slotted member slidably mounted upon the rod adjacent the end of the tubular member and connected to the cut-off valve; a clamping member slidably 'pivotally mounted upon the rod adjacent the slotted member; nuts threaded onto the outer end of the rod for adjustably holding the clamping member in proximate relation to the slotted member, said slotted member being rigidly clamped when the tube and rod are expanded by heat from the burning jet, and released for sliding movement when the tube and rod contractupon cooling after said jet is extinguished whereby the cut-ofl valve may be retained in open position while the pilot is burning and released to a closed position when the pilot becomes extinguished.

5. The combination with a gas burner, supply pipe, and ravity actuated cut-off valve mounted in t e supply pipe for controlling the flow of gas therethrough to the burner, of a pilot burner mounted adjacent the burner, said pilot burner comprising a tubular member; a cap secured upon one end of the tubular member and apertured to direct burning gas therefrom over the burner; a rod extending through the tubular member; said rod being secured at one end upon the cap and extending outwardly through the opposite end of the tubular member in slidable engagement therewith, the rod and tubular members made of metals adapted to cause a greater expansion of the tubular member than of the rod when heated by the burning jet; a slotted member slidabl mounted upon the rod adjacent the end 0 the tubular member and connected to the cut-ofi valve; a clamp ing member slidably and pivotally mounted may be retained in open position while the pilot is burning and released to a closed position when the pilot becomes extinguished; and means for moving the clamping member to release the slide member.

6. The combination with a gas burner su ply pipe, and gravity actuated cut-01f va ve mounted in said supply pipe for controlling the flow for gas therethroughto the burner, of a pilot burner mounted adjacent the burner, and arranged to direct a pilot flame over the burner, said pilot burner comprising a tubular member; a rod extending through said tubular member, said rod being secured within one end of the tubular member and extending outwardly in slidable engagement with the other end of the tube to ermit relative movement thereto due to a ilference in the amount of expansion when the tube and rod are heatedbya pilot flame; a retaining member mounted upon the outwardly extending end of the rod and connected to the valve, said retaining member being clamped in retaining position to hold the valve when the rod and the tube are expanded by heat and released to permit closing of the valve when said members contract upon cooling.

In witness whereof I hereby set my signature.-

GEORGE A. TUGKZ 

